The following is a description of three types of vacuum cleaners which differ in design and operation. All of them have as common features a motor-driven fan, a dust collection chamber, and one or more floor treatment devices which are each adapted for a particular purpose.
The canister vacuum cleaner has a housing which can be moved on the floor to be cleaned on wheels and/or runners. The housing contains the motor-fan unit and the dust collection container. The floor treatment device, here referred to as floor nozzle, is connected to the dust collection chamber via a suction hose, and possibly a suction wand connected therebetween. During vacuuming, the housing is moved to the desired position by pulling on the suction wand.
In a stick vacuum cleaner, the motor-fan unit and the dust collection container are also disposed in a housing. A suction wand extends from one end of the housing, connecting the floor nozzle to the dust collection container, and a handle used to maneuver the housing to the desired position extends from the other end.
Uprights do not have as strictly divided a configuration as the two aforementioned types. One feature of an upright is a movable base unit which carries an upper body containing a large dust collection container. The two parts are tiltable relative to each other and can usually be locked in a parked position in which the upper body is nearly upright when the base unit is located on a horizontal floor in a position of use. In this position, the upright stands unsupported. During vacuuming, the above-described locked engagement is released, and the upper body is tilted through a certain angle to an operating position. The tilt angle depends on the height of the user and on the particular purpose of use. A handle is provided on the upper body for maneuvering the entire appliance. The motor-fan unit may be mounted at different locations. WO 2007/008770 A2, for example describes securing the fan directly to the upper body. This reduces the ease-of-use because this heavy component produces a torque about the tilt point, which the user must counteract throughout the vacuuming operation. The upright described in WO 2007/008770 A2 has the further drawback is that it is difficult to move from a straight path of travel into a curved path of travel. In WO 2004/014209 A1 and EP 0 708 613 A1, the fan is configured as a separate unit. Providing a point of rotation between the upper body and the upper region of the fan (EP 0 708 613 A1), or mounting the fan in a rotatable, spherical housing (WO 2004/014209 A1) enables the upright to move along curved paths, thereby improving maneuverability.